Known lane keeping technologies control a vehicle to keep the vehicle within a target lane in an automatic steering mode that automatically performs at least some of driver's steering operations.
For example, Japanese Patent Application Publication No. 2015-20604, which will be referred to as a published document, discloses a motor control apparatus in a vehicle control system. The motor control apparatus disclosed in the published document performs lane keeping control that generates automatic steering torque for a motor; the automatic steering torque causes the vehicle to travel along a target lane.
The motor control apparatus also performs power-steering control that generates assist torque for the motor to thereby reduce the load on driver's steering operations.
While executing the automatic steering, the motor control apparatus determines a driver's steering intervention upon detection of steering torque, and converts the steering torque into an intervening coefficient based on predetermined conversion information. Then, the motor control apparatus controls the automatic steering torque using the intervening coefficient. This control enables, even if there is a driver's intervention, the lane-keeping control to be carried out without driver's feeling of strangeness.